| Baby Eddie | |
 | |
| Gender | Male |
| Hair Color | Brown (though completely bald) |
| Relationship | None |
| Family | Jimmy Neutron, Hugh Neutron, Judy Neutron, Anabelle Neutron, Granny Neutron, Aunt Amanda |
| Friends | Villains |
| Likes | Evil, Power, and Killing People |
| Dislikes | The Neutron family |
| Voice Actor | Mark DeCarlo |
Baby Edward "Eddie" Neutron was Jimmy's evil baby cousin, who has a grown man's voice; just when he talks in his normal voice, he then suddenly talks in a baby voice by saying, "Goo!"..
Eddie is only 17½ months old. Eddie believes that he is a lot smarter than Jimmy. In his first appearance in "Clash of the Cousins", Eddie schemed to kill his family by putting a bomb in the birthday cake. But his plan failed. He was voiced by Mark DeCarlo who also voices Jimmy's dad, Hugh Neutron. Paul Greenberg who did the voice Brobot also voiced him by providing bab styley voice effects.
Despite his intelligence and adult voice, he is still mentally immature as he is physically. He cries when upset, gets angry when Jimmy destroys his rattle, demands his Sippy cup and always needs to be changed. He last appears in The League of Villains]].